Spectrin beta chain, non-erythrocytic 4 (SPTBN4)

Spectrin beta chain, non-erythrocytic 4 (SPTBN4) is a cytoskeletal scaffold protein that links the cell membrane to the actin cytoskeleton, playing a critical role in the structural organization of neurons, especially at the axon initial segment and nodes of Ranvier[1][4][5]. It enables clustering and localization of essential ion channels (notably sodium and potassium channels) in polarized neuronal regions. Loss-of-function variants in SPTBN4 cause a rare, autosomal recessive neurodevelopmental disorder characterized by hypotonia, peripheral neuropathy, and deafness (NEDHND), reflecting its essential role in nervous system development and function[2][3][5]. The gene is considered crucial for cytoskeletal integrity and neuronal excitability, but it is not currently regarded as a direct therapeutic target, and there are no approved drugs that act on SPTBN4[2][3][5]. Mutations are typically used as genetic biomarkers for diagnosis in affected families.

Other names

Spectrin beta, non-erythrocytic 4Beta-IV spectrinSpectrin, non-erythroid beta chain 3SPTBN3 (frequently misused, but a separate gene)KIAA1642SPNB4spectrin beta chain, brain 3spectrin, non-erythroid beta chain 3CMNDNEDHNDQV